Question

The error and the correction to be made when the zeroth division of the head scale in a screw gauge is above index line of the pitch scale ___________________.

• A. positive, negative
• B. negative
• C. negative,positive
• D. positive

Answer 1

The correct option is C negative,positive

In screw gauge :
Negative zero error If the zeroth division of the head scale is above the index line the error is said to be negative and the correction has to be positive.
Positive zero error If the zeroth division of the head scale is below the index line of the pitch scale, the error is said to be positive and the correction is negative.